This circuit makes use of a transconductance operational amplifier from the 90s. Formula for the calculation of the components is given next to the diagram.
This simple circuit applies to any sensitive SCR. We found it in 1982 Maplin documentation. ...
The photocontrol that we give in this project of a 1982 documentation allows to activate a circuit...
This interesting bandpass filter using an operational amplifier 741 has its cutoff frequency...